THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

[18:00:02]

WOLF BLITZER, CNN ANCHOR: Rejecting Trump. A senior Republican senator comes out against Donald Trump. Susan Collins cites -- and I'm quoting now -- "his constant stream of cruel comments" and says she has to accept what she calls the unpleasant reality that Trump won't change.

Will more Republicans turn against their nominee?

"Many people are saying," Donald Trump's repeated use of that phrase coming under scrutiny. Critics charge he's using it to camouflage distorted claims. Now it's even sparking a Twitter trend. Who are these people? Do they even exist?

And spied from the sky. Satellite photos reveal what appears to be reinforced airplane hangars on islands built by China in disputed territory. The buildings are big enough to house any of China's fighter jets, even though the country promised it won't militarize the islands. How will the U.S. respond?

We want to welcome our viewers in the United States and around the world. I'm Wolf Blitzer. You're in THE SITUATION ROOM.

ANNOUNCER: This is CNN breaking news.

BLITZER: Breaking news.

There's alarm tonight by remarks by Donald Trump that some see as a threat Hillary Clinton's life, but which Trump supporters insist were only encouraging gun rights supporters to vote.

At a rally a short time ago in North Carolina, Trump falsely said Hillary Clinton wants to essentially abolish the Second Amendment and he warned that as president she will pick supposed justices who will do it.

Trump then said -- and I'm quoting -- "There's nothing you can do, folks," but he added, maybe what he called Second Amendment people can do something to stop Clinton. Also breaking, new polls just released that show Hillary Clinton is

leading Donald Trump in three key Midwest battleground states. The NBC/Wall Street Journal and Marist polls show Clinton modestly ahead in Iowa and Ohio and holding a double-digit lead in Pennsylvania.

Amid all of this, another top Republican lawmaker is now saying she will not be voting for Trump. Senator Susan Collins of Maine tells CNN she now believes the GOP nominee is unfit to be president, that his values represent a threat to the Republican Party, and that he could make the world more dangerous.

We're covering all of that, much more this hour with our guests, including Trump supporter and Republican Congressman Duncan Hunter. And our correspondents and expert analysts, they are also standing by.

But let's begin with those remarks by Trump that one Democratic senator is calling an assassination threat against Hillary Clinton.

CNN political reporter Sara Murray is with the Trump campaign in North Carolina right now.

Sara, Trump's team is moving quickly to try to put out this latest fire.

And it didn't take long to see the outcry from political observers who saw Trump's comment that Second Amendment supporters should do something about Hillary Clinton as a call violence. The Trump campaign quickly moved to insist that is not what they meant.

One thing is clear, Wolf, this is the kind of dust-up that has once again knocked Donald Trump off message on a week he was hoping to talk about the economy.

(BEGIN VIDEOTAPE)

MURRAY (voice-over): Donald Trump setting off controversy with another off-hand comment, one some believe amounts to a violent threat against his political opponent.

TRUMP: If she gets to pick her judges, nothing you can do, folks, although the Second Amendment people, maybe there is. I don't know.

MURRAY: Trump's suggestion that Second Amendment voters have the power to stop Clinton instantly raising questions about what the candidate meant, whether he was simply looking to coalesce gun supporters behind him or if he meant something more nefarious.

The Clinton campaign quickly seizing on Trump's comment as a sign the GOP nominee is inciting violence, saying in a statement: "This is simple. What Trump is saying is dangerous. A person seeking to be the president of the United States should not suggest violence in any way."

The Trump campaign swiped back, billing the issue as a media-driven controversy, and insisting Trump was simply trying to rally gun voters.

In a statement, the Trump camps says: "It's called the power of unification. Second Amendment people have amazing spirit and are tremendously unified, which gives them great political power and this year they will be voting in record numbers and it won't be for Hillary Clinton. It will be for Donald Trump."

But Trump's latest off-the-cuff comment on a week when he was striving to stay on message is exactly the sort of flare-up giving members of his own party pause. The latest defector, Senator Susan Collins of Maine, who penned an op-ed saying she will not vote for Trump.

The GOP senator even telling Jamie Gangel that Trump poses a risk to the nation.

SEN. SUSAN COLLINS (R), MAINE: Donald Trump, in my judgment, would make a perilous world even more dangerous.

[18:05:05]

MURRAY: Her announcement coming soon after a group of 50 GOP national security officials said they can't back Trump either, arguing he would put at risk our country's national security.

Trump quickly dismissed the snub.

TRUMP: These are 50 people that have been running our country forever and they said, we can't support Donald Trump.

The reason they can't? You know why? Because I'm not going to hire these people. I don't want these people.

MURRAY: But as he struggles to keep his party in line and lags in the polls, Trump says the key to victory is more of the same.

TRUMP: I have always had a good temperament. And it's gotten me here. We beat a lot of people in the primaries. And I certainly don't think it's appropriate to start changing all of a sudden when you have been winning.

MURRAY: As well as finding openings to hammer his Democratic opponent, today mocking Clinton for saying she short-circuited her handling of the e-mail issue.

TRUMP: Could you imagine if I said that I short-circuited? They would be calling for my execution, electric chair. They would bring back the electric chair. It's one thing to make bad decisions. It is another thing to be wacky and make bad decisions.

(END VIDEOTAPE)

MURRAY: Now, of course, the Clinton camp has been taking shots at Trump as well.

They put out a statement last night saying Hillary Clinton will appear at all three debates, goading Donald Trump to say whether or not he will also be on stage. He told "TIME" today that he absolutely will take part in three debates, but says he still has conditions, still raising the question of whether he might actually be there.

As for that Second Amendment fiasco, we will be watching here tonight in a couple minutes when Donald Trump begins to see if he tries to further clarify remarks from earlier today -- Wolf.

BLITZER: All right, we will see what he does. Thanks very much, Sara, for that.

Trump's unconventional style includes the way he speaks. And there's one phrase he often uses that is now coming under scrutiny.

Our chief political correspondent, Dana Bash, is with us.

We're talking about Trump's habit of declaring many people are saying.

But now one phrase Trump uses as a crutch, at least seems to, when going after someone or something has taken on a life of its own.

(BEGIN VIDEOTAPE)

BASH (voice-over): It has long been a staple of Trump speak.

TRUMP: Some people have been saying that.

A lot of people are saying that.

Half the people in this room are saying that. Some people. I don't know.

BASH: Then this tweet. "Many people are saying that the Iranians killed the scientist who helped the U.S. because of Hillary Clinton's hacked e-mails."

That harsh allegation, using only "many people are saying" as his proof, made the catchphrase an instant Internet sensation. A #manypeoplearesaying hashtag went viral, becoming a forum to mock Trump. Hillary Clinton's spokesman Nick Merrill tweeting: "Many people are saying that a unicorn is housed in a cage above Trump Tower."

The band Spoon: "Many people are saying our next album will heal the sick and end all war. It's just what many people are saying." But beneath the sarcasm is a serious question. Why does Trump send conspiracy theories into the ether with only a version of many people are saying to back it up?

TRUMP: Is he a natural-born citizen? Some people -- I don't know.

BASH: Sometimes, it's about knocking an opponent off message, like during the primaries when Trump questioned Canadian-born Ted Cruz's eligibility to be president.

TRUMP: A lot of people think you have to be born here. You have to be born on this land.

BASH: Cruz, who was then gaining on Trump in Iowa, denounced Trump's allegation.

SEN. TED CRUZ (R), TEXAS: The legal issue is straightforward. the son of a U.S. citizen born abroad is a natural-born citizen.

BASH: Other times, it appears Trump uses it to change the subject when he's getting bad press. Trump's Monday afternoon tweet Connecting Clinton to an executed Iranian scientist came little more than an hour after "The New York Times" first reported about a letter signed by 50 GOP national security experts warning Trump would be a dangerous commander in chief.

TRUMP: A lot of people are very skeptical as to what happened and how he died.

BASH: When Trump started focusing on Clinton after he locked up the GOP nomination, he used his some people say phrase to road-test conspiracy theories from the 1990s, like questioning whether Clinton aide and friend Vince Foster really committed suicide, Trump telling "The Washington Post" -- quote -- "There are people who continue to bring it up, because they think it was absolutely a murder. I don't do that, because I don't think it's fair."

Beyond why Trump does this, the question of, do these people exist, and, if so, who are they? One source familiar with how Trump operates tells CNN sometimes those people are some of Trump's 10.8 million Twitter followers, many of whom constantly send him ideas and suggestions.

Remember, this Trump M.O. worked for him in the GOP primaries and even before he ran in 2011, seizing on the Obama better movement.

[18:10:01]

TRUMP: A lot of these birther are just really quality people that just want the truth.

BASH: Still, scroll through Trump's Twitter feed, and you realize he's relied on the phrase for years even to promote his businesses -- quote -- "Many people have commented that my fragrance Success is the best scent and last the longest. Try it and let me know what you think." (END VIDEOTAPE)

BASH: Now, even though Trump's many people are saying tweet yesterday spawned an avalanche of criticism and mockery on Twitter and Facebook all day today, Wolf, Trump himself has yet to respond. Even though he's a Twitter fanatic, we have not seen anything on social media.

BLITZER: We will see if that happens. All right, Dana, thanks very much. Good report.

REP. DUNCAN HUNTER (R), CALIFORNIA: Hey, thanks for being -- for having me with you. I appreciate it, Wolf.

BLITZER: All right, good.

We got a lot of issues to go through. But let me go through this latest commotion that is out there. I want you to listen carefully to what Donald Trump said at a rally a couple hours or so ago, because it's generated a lot, a lot of interest. Listen to this.

TRUMP: By the way, and if she gets to pick -- if she gets to pick her judges, nothing you can do, folks, although the Second Amendment people, maybe there is. I don't know.

(END VIDEO CLIP)

BLITZER: All right, Congressman, what do you think he meant by that?

HUNTER: What I think he means by that is what every politician, anybody running for office around the world has probably said multiple times at multiple events: We can stop this person.

And that's it. Wolf, I don't -- I don't think there's anything nefarious. I think the media is blowing this up. I don't think it's a story at all, frankly.

But, I mean, I can't count the number of times that I have said at my events to my people who are going for me, hey, we can stop my opponent. We can stop Hillary Clinton. There's something we can do about this person getting elected.

What that means is, we're going to vote for me, Donald Trump, and not get Hillary Clinton elected and that's what we can do about it.

That was pretty easily understood by me. I'm a Second Amendment person. So I guess he's talking about me when he says Second Amendment people. I didn't take anything from that that had anything to do with assassination or trying to, you know, commit some kind of violent act.

And, too, Wolf, you know this. When you talk politics, you use metaphors and analogies all the time. And if you -- especially me. I did three tours overseas. I used military analogies and metaphors all the time. If somebody wanted to take those metaphors or analogies or take what I say, and make them literal or try to find something that said, hey, Duncan Hunter is trying to promote acts of violence against people, they would have taken it totally out of context of what I meant.

But this is how politics is, though. But I think that the media has really jumped on this and is creating something over nothing, which is what the media does.

BLITZER: It's not just the media. It's politicians, critics of Donald Trump.

Chris Murphy, the senator from Connecticut, he tweeted this in response to what Trump said. He said: "Don't treat this as a political misstep. It's an assassination threat, seriously upping the possibility of a national tragedy and crisis."

And General Michael Hayden, the former head of the CIA and the National Security Agency, he said this. This what he told our Jake Tapper.

(BEGIN VIDEO CLIP)

GEN. MICHAEL HAYDEN (RET.), FORMER CIA DIRECTOR: That was more than a speed bump. All right? That's actually a very arresting comment.

If someone else had said that outside the hall, he'd be in the back of a police wagon now with the Secret Service questioning him.

(END VIDEO CLIP)

BLITZER: All right. So those are serious, serious statements you just heard, Congressman. Go ahead and react.

HUNTER: Well, number one, freedom of speech is one thing. Right?

I think General Hayden -- I respect him greatly. I think he's wrong on this one. I don't think you hull somebody away for saying that we're going to get out the vote and stop Hillary Clinton from becoming president. It's that simple to me, Wolf.

I think General Hayden is wrong, and I understand what the senator was saying, too, but this is politics. This is presidential politics. People are going to make as much of a deal as they can about something like this. I don't even think that it was Trump misspeaking. I think Trump said what he meant, and what he meant was, we can stop Hillary Clinton from being elected.

We can stop Hillary Clinton from being the next president who chooses who's going to sit on the Supreme Court over the next four years.

(CROSSTALK)

BLITZER: You know, Congressman, the Secret Service takes very seriously threats of assassination to a president or presidential nominee.

HUNTER: Sure.

BLITZER: In this particular case, if you read carefully...

HUNTER: Wolf, there was no violence mentioned there.

(CROSSTALK)

BLITZER: Let me just point out what the critics are saying. Then I will give you a chance to respond.

He was saying if she gets to pick her judges. That means, if she gets to pick judges, she's already the president of the United States. She can pick a Supreme Court justice. "There's nothing you can do, folks, although the Second Amendment people, maybe there is. I don't know."

[18:15:05]

"I don't know," that's the way he said it. So he wasn't talking about necessarily people going out and voting right now. He was saying, what happens if she's president of the United States? There's nothing anyone can do about the judges she's going to pick, unless the Second Amendment people, maybe there is.

You understand why they're suggesting he was entering into this, this awful world of potential violence?

HUNTER: Sure, Wolf.

So, I would disagree with you on this point. You're treating Mr. Trump's words like he is the most articulate person who's ever graced our ears with his words, and that is not true. He is not a politician. He is not a person like you, who's very articulate, very well-spoken. He's a businessperson who is running for president.

So, I don't think that the way that he said that and the sequence of his statements, I'm not going to judge him on that, because I don't think that's what he meant. And I think that he can be inarticulate at times.

What I think he just meant by that, and by what he said, is, we can stop her from becoming president. We can stop Hillary Clinton from being the person who picks the next Supreme Court judges.

But so let's say that he was an English professor with a Ph.D. in grammar. Then I think that we could go through it with this way and dissect what he said literally based off the sequence that he said it.

But I'm not doing that with Mr. Trump, because you can't do that with Mr. Trump. Right? Sometimes, he says things that...

BLITZER: All right.

HUNTER: And the way it comes out is not what he means. This is not an assassination talk. It's not a talk about violence. It's talk about beating Hillary Clinton.

BLITZER: But you know he wants to be president of the United States.

And, as you know, you're a politician, words do matter. You have to be precise in what you're saying.

HUNTER: No, Absolutely.

But that is what makes Trump much different than even me. I'm not the most articulate guy in the world, but Trump hasn't ever run for office anywhere. He is a businessperson. And he misspeaks a lot because he doesn't speak for a living, like you and I do to some extent.

So, I can see where this happens, and I think it's going to happen more, too, Wolf. I think this is not going to be the last time that this happens. It's certainly not the first.

BLITZER: That's right. Some of his advisers -- and you know this, Congressman -- they want him to stick to scripted speeches, as he did yesterday at the Detroit Economic Club, and not necessarily go off the cuff.

But hold on for a moment, because there's more questions. I want to get to some of the national security issues that have come out. You heard what Susan Collins, the Republican senator from Maine, has to say.

Much more with Duncan Hunter right after this.

(COMMERCIAL BREAK)

[18:21:49]

BLITZER: We're following the breaking news, remarks by Donald Trump that critics are taking as an assassination threat against Hillary Clinton.

Trump said at a rally a little while ago that gun rights supporters could stop Hillary Clinton from abolishing the Second Amendment. The Trump campaign says he was talking about the voting power of what he called the Second Amendment people.

We will have more on that coming up.

I want to continue our conversation now with Republican Congressman Duncan Hunter of California. Congressman, Republican Senator Susan Collins of Maine, she announced

she will not support Donald Trump and she said -- and I'm quoting her now -- she said: "The unpleasant reality that I have had to accept is there that will be no new Donald Trump, just the same candidate who will slash and burn and trample anything and anyone he perceives as being in his way or an easy scapegoat. Regrettably, his essential character appears to be fixed. He seems incapable of change or growth."

Talk to us how he's evolved, from your perspective, through this campaign, how he's grown.

HUNTER: Yes, we're not going to put her down as undecided, right?

I respect Senator Collins' decision there. But he has grown and in this way, Wolf. He is not a politician. He's not a person on the news that talks for a living. He usually reads scripts if he's on television. He's a businessman who is running for president.

In the beginning, I mean, if we chronicled his gaffes or his mistakes from when he first started in the Republican primaries, when this whole thing very first started, those would be many, many more than we would calculate now towards the end.

So, I think he's simply getting better at articulating what he's thinking, putting that into words. And that takes time. In fact, for most people, it takes years of speaking publicly to be able to really translate cogently what you're thinking and put those into words, like I'm doing right now.

That takes a long time and it takes practice, just everything else. I think he's growing in that way. Number two, I think he understands more now the complexities of the world than he did when he first ran. But at the same time, things are not overly complex.

And I think that when you talked about those 50 signatories, those GOP foreign policy, national security experts and former ambassadors and so forth signing this letter on Trump, I think it's unfair, frankly. I think if you look back to 2000, the year 2000, the Iraq wars, which I fought in twice, Afghanistan, which I fought at once, you look at those and the framework in which the United States operated, both foreign policy, State Department-wise and defense-wise, and what we did there for national security, I don't think Trump believes that that works.

So, he as president is allowed to say -- or him as the candidate is allowed to say, look, I don't agree with the framework in which we have been fighting wars in the Middle East and Southwest Asia, and those people who were the architects of the way that we're still fighting wars over there, they're allowed to say that they don't like me, because I think that they're wrong in the first place.

He also added in ISIS and some other stuff, which wasn't quite right, but I think he's right on his first points.

[18:25:01] BLITZER: So, here's the question. You just said Donald Trump is not

necessarily as articulate out there when he's speaking off the cuff, not reading a prepared speech from a teleprompter. He's doing that, by the way, a little bit more often lately.

But over the past year-plus, he's been doing most of his rallies just speaking, got some notes in front of him. But you say he's not necessarily all that articulate. Do you trust Donald Trump's national security, foreign policy judgment more than these other Republican national security advisers, these foreign policy experts who signed that letter saying they cannot support Donald Trump?

HUNTER: Yes, in this way, Wolf.

My dad was chairman of the Armed Services Committee during the Iraq War. My dad is not one of those signers. Senator Sessions is not one of those signers. Chairman Mac Thornberry, who is chairman of the Armed Services Committee now, is not one of those signers.

So, I could give you 50 names of people who do support Donald Trump, General Flynn, General -- I mean, I could go through some other generals names, without knowing whether they wanted to be mention here on TV or not.

But my point is, I can give you 50 smart people who specialize in foreign policy and national security and say they are behind Trump.

So, just because a group of folks with very big names, I will give them that, get together and say, we're not going to vote for this guy, that doesn't sway me whatsoever. And it's sure not going to sway the millions of people that have lost their jobs is this country.

So, I think that they're speaking to a much different group of people than the majority of folks that are going to vote for Donald Trump. They don't care what the former mid-level ambassador to Turkey has to say about Trump's foreign policy.

What they care about is their jobs and making sure that we put Americans first again.

BLITZER: But some of these people who signed that letter were CIA directors, directors of national intelligence, a former homeland security secretary. There's a few big shots who signed that letter as well, pretty well-known types.

We don't have to go through all of that. And I know you speak from the heart. You're a member oft Armed Services Committee. You served three combat tours of duty in Iraq and Afghanistan as well.

But let me ask you a final question on Donald Trump's tax returns. Sean Duffy, he's a Republican from Wisconsin. I assume you know Congressman Sean Duffy.

HUNTER: Yes.

BLITZER: He was with us 24 hours ago in THE SITUATION ROOM, and he said he believes Donald Trump should release his tax returns, which all presidential candidates have done since the '70s. Do you agree with Sean Duffy?

HUNTER: No, I don't think that Trump needs to show his tax returns.

And if I recall correctly, Wolf, he said he would once he was done being audited. So I think that's a fairly straightforward answer. But, no, I don't care about Trump's tax returns, truly.

This is where -- we're dealing with a type of person running for president right now, a billionaire businessman that is different than the majority of candidates, like the Clintons who got into office not poor, but not wealthy, then got out of office and got extremely wealthy, whereas Trump's coming into it very wealthy in the first place.

So, I think that that's different. But, no, I actually don't care whatsoever about his tax returns being shown.

BLITZER: All right, Duncan Hunter, thanks very much.

HUNTER: Thanks, Wolf.

BLITZER: Disagreeing with Sean Duffy.

Appreciate it, Duncan Hunter of California.

We're following the breaking news. We will have more on Donald Trump's remarks that critics say sound like a threat against Hillary Clinton's life. We will have Hillary Clinton's response to all of that. Stay with us.

(COMMERCIAL BREAK)

BLITZER: More on the breaking news right now. Donald Trump's remark just a little while ago that gun rights supporters could stop Hillary Clinton from enacting gun control.

[18:33:14] Trump's critics say he was suggesting violence. His campaign says Trump was talking about the voting power of Second Amendment supporters.

Our chief political correspondent, Dana Bash, is back with us to talk about it, along with CNN politics editor Juana Summers and "Washington Post" assistant editor David Swerdlick. Also joining us, our CNN special correspondent, Jamie Gangel.

Let me play the clip that has generated all this commotion, Dana. Then we'll discuss.

(BEGIN VIDEO CLIP)

DONALD TRUMP (R), PRESIDENTIAL NOMINEE: Hillary wants to abolish -- essentially abolish the Second Amendment. By the way, and if she gets to pick -- if she gets to pick her judges, nothing you can do, folks. Although, the Second Amendment people, maybe there is. I don't know. But...

(END VIDEO CLIP)

BLITZER: All right, Dana, how's this going to play out?

DANA BASH, CNN CHIEF POLITICAL CORRESPONDENT: You know, I think it's -- if this was a kind of one-time thing, that Donald Trump does something that everybody goes, "Oh, my gosh" to, then maybe it would be kind of more of a blip. So I don't think that this is going to change very much when it comes to the trajectory of the campaign.

However, I do think, look, I mean, maybe he was kidding. Maybe he meant something else. When I watched that, I went, "Oh, my goodness." And you could actually see one of the guys behind him kind of wincing. Or looking over at the person with him going, "Oh, my gosh. Did he just say that?" You know.

Rudy Giuliani, is out with Donald Trump as we speak, of course, blaming the media and saying that we're creating this. And it is true that the Democrats have jumped on this in an almost, you know, expansive and extensive way. So it does kind of make it more partisan.

BLITZER: And it will be interesting to see if Donald Trump himself tries to clarify and fix this and move beyond it.

BASH: Well, they have planned a statement. They have put out a statement.

[18:35:03] BLITZER: I saw the statement that he put out. And I'll read the statement just to be precise: "It's called the power of unification. Second Amendment people have amazing spirit and are tremendously unified, which gives them great political power. And this year they will be voting in record numbers, and it won't be for Hillary Clinton. It will be for Donald Trump." That's from Jason Miller, senior communications adviser to the Trump campaign. I'm just curious, given all the discussion that has developed over these past few hours...

BASH: Sure we haven't heard of last of this.

BLITZER: ... if Trump decides to clarify it himself, and we'll monitor that, of course, closely.

Something else he said today, David, generating buzz, not as much as this, when he said Hillary Clinton, talking about voter I.D. and a rigged system. He said Hillary Clinton voters might vote 15 times or something. Then he said, "I will not tell you to vote 15 times. I will not tell you to do that."

You know, it's generated some commotion out there, as well. Why is he even talking about the suggestion that a presidential election could be rigged?

DAVID SWERDLICK, ASSISTANT EDITOR, "WASHINGTON POST": Yes. He's trying to underscore this theme that he has worked throughout the primaries and now the general, that the system is rigged, that the average person can't get a break. He's sort of speaking as a man of the people and that, whether it's debates or primaries or party rules, that the deck is stacked against regular guys like him, and this is just one more way for him to do that.

BLITZER: Juana, there's a bunch of Republicans now, Susan Collins being the latest in the Senate; elsewhere, these national security advisors are saying they're not going to be able to vote for Donald Trump. Is this just the beginning or are we going to see more of that?

JUANA SUMMERS, CNN POLITICS EDITOR: I think that still remains to be seen. All the people you've listed, the people who signed that letter, Senator Collins and the five other senators, I believe it is, who have said they won't back their party's nominees, those are the people who are in the establishment. They've been with a party a long time.

My big question, when we're looking at this trend, is whether or not it trickles down to voters. CNN did a poll right after the Democratic convention. And in that poll more than one-third of Republicans -- I think it's 35 percent -- said they would not be proud to see Donald Trump as president if he wins the election in November. And that's really striking to me. Because if Donald Trump can't win over the overwhelming majority of members of his own party, he just can't get the votes he needs to win the election.

BLITZER: Yes, we got -- we got -- we'll show you the six Republican senators who are already publicly come out and said they won't be able to vote for Donald Trump: Susan Collins, Jeff Flake, Lindsey Graham, Ben Sasse of Nebraska, Mark Kirk of Illinois, Mike Lee of Utah, more potentially could be on the way.

Jamie, you had the first television interview with Senator Collins earlier today. She had a strong message to Republicans who might say she is betraying her party. I want you to listen to this clip.

(BEGIN VIDEO CLIP)

SEN. SUSAN COLLINS (R), MAINE: I would say to them that Donald Trump does not represent the values or the heritage of the Republican Party, and we should not be afraid to say that, and indeed, there is a risk to the Republican Party if Donald Trump is perceived as embodying our values.

(END VIDEO CLIP)

BLITZER: So why did she decide to do this right now?

JAMIE GANGEL, CNN SPECIAL CORRESPONDENT: So I thought that was just interesting, Wolf, what she did. She's not betraying the Republican Party, she says; Trump is the one who's betraying the Republican Party.

Senator Collins has been thinking about this for a long time. I've talked to her over the last several weeks, months, and she's been very public about her concern about it.

She says the straw that broke everything was what Donald Trump said about the Khan family, those Gold-Star parents of the Muslim-American soldier that was killed in Iraq. That she just could not abide by that.

But she also mentioned she was very upset about his mocking the "New York Times" reporter who has disabilities. She was upset about the way he treated the Indiana judge, Judge Curiel of -- who is of Mexican heritage, and said he couldn't be fair. I think all of these things built up.

She also serves on the Senate Intelligence Committee, and she used to be the chairman of the Homeland Security Committee, and there is no question she is also very, very concerned that the -- Donald Trump could be dangerous. She says he doesn't have the temperament; he doesn't have the judgment. And she feels that, if he was in the international arena, she said repeatedly, things could spiral into a very dangerous cycle.

BLITZER: But she also told you she's not going to vote for Hillary Clinton either. Right?

GANGEL: Right. So that was a change. The door was open just a little crack a couple of weeks ago. She told me that there was a small possibility that she would vote for Hillary Clinton.

She has now said that she will not do that. She's taking a look at the Libertarian ticket. She likes William Weld. She does not know Gary Johnson; she has some concerns.

And then said that she might very well write someone in. And I tell you that on her short list of people that she might write in is the man that she endorsed at the beginning of this campaign, and that's Jeb Bush. And the sense that I got today is, we can expect a write-in vote from her, but she also has a certain luxury in that Maine is likely -- it's not a battleground state in the classic sense of Ohio or Florida.

BLITZER: All right. Guys, everyone stay with us. We have more information coming in. New polls showing Hillary Clinton leading in some of the elections, most important, swing states; targeting other states that usually vote Republican. Stay with us.

(COMMERCIAL BREAK)

[18:45:25] BLITZER: The breaking news hour: the Trump campaign facing a new uproar sparked by the Republican nominee. Trump remarks at a rally that what he called the Second Amendment people could stop Hillary Clinton from enacting gun control. Some top Democrats say that was a threat on Hillary Clinton's life. The Trump campaign says he was encouraging voter turnout by gun rights supporters.

Our senior Washington correspondent Jeff Zeleny joining us with more right now.

Jeff, has Hillary Clinton addressed these latest Trump comments?

JEFF ZELENY, CNN SENIOR WASHINGTON CORRESPONDENT: Wolf, she has not addressed these comments herself. She was asked twice this afternoon, and did not respond. But just a few minutes ago, vice presidential candidate Tim Kaine harshly condemned Trump's words, calling it a window into the soul of a person who is just temperamental and not suited to the task.

But, Wolf, all this is coming as Clinton is trying to broaden her appeal and not only to Democrats.

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ZELENY (voice-over): Hillary Clinton is casting a wider net tonight.

HILLARY CLINTON (D), PRESIDENTIAL NOMINEE: Thank you for the work you do every day.

ZELENY: Searching for new Republican supporters and newly competitive red states possibly up for grabs in the wake of Donald Trump. The Clinton campaign's concerted effort to recruit some Republicans peeling off Trump is paying off at least in small ways.

Two prominent Republican environmentalists who ran the EPA during the Nixon, and George H.W. Bush administrations announced support today for Clinton. They said Trump has shown a profound ignorance of science, particularly on climate change.

Yet, not all Republicans coming out against Trump are turning toward Clinton, including Republican Senator Susan Collins of Maine.

SEN. SUSAN COLLINS (R), MAINE: I have a lot of concerns about Hillary Clinton, and I am not going to support her.

ZELENY: CNN has learned the Clinton campaign is also eyeing new investments in Georgia and Arizona, exploring whether Trump's challenges have created a realistic opening in Republican territory. Those are two red states with a high share of Hispanic and black voters. Democrats believe they can flip. It's a delicate dance for Clinton. In Florida today, blasting GOP congressional leaders for not signing off on Zika funding.

CLINTON: Get a bill passed. Get a bill that is focused on combating Zika passed.

ZELENY: Suddenly overshadowed by another man -- the father of Pulse nightclub shooter Omar Mateen sitting just behind Clinton, watching as she talked about the nation's mass shooting, killing 49 people in June.

CLINTON: I know how many people, family members, loved ones and friends are still grieving.

SEDDIQUE MATEEN: They shouldn't be surprised. I love the United States. And I've been living here for a long time.

ZELENY: He said he supports Clinton.

MATEEN: Clinton is good for United States, versus Donald Trump.

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ZELENY: Now, Mateen, a native of Afghanistan, is a U.S. citizen. He has said incredibly provocative statements in the past. Clinton is not disavowing those words tonight, Wolf. Her campaign is focusing on the provocative statements of her rival instead.

BLITZER: Jeff Zeleny reporting for us -- thank you.

Just ahead, a possible military buildup by China. What this new satellite images are now showing.

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[18:53:57] BLITZER: There are disturbing new signs tonight that China may be carrying out a military buildup on manmade islands it constructed in disputed waters.

Our chief national security correspondent Jim Sciutto is working this for us.

Jim, there is a lot of concern about what China may be up to right now.

JIM SCIUTTO, CNN CHIEF NATIONAL SECURITY CORRESPONDENT: These are brand-new satellite photos. They were released by CSIS, a think tank here in Washington. Here's what they show that these islands really created out of nothing in the South China Sea now have hangars able to accommodate the biggest warplanes in China' arsenal.

Let's dial it back a bit. These are current pictures. Let's go back to March of last year where they were constructing these and myself and a team were flying over them in a U.S. spy plane. They took what were essentially just rocks, built up out of thousands of acres across the South China Sea. By the end of last year, they'd added this runway. That runway about two miles long and can accommodate any aircraft in the Chinese military fleet.

Now, let's toggle forward to just June of this year. They have these hangars here. These can accommodate all of the fighter jets in the people's liberation fleet.

[18:55:04] These can accommodate even their warplanes, their refuelers. And there are also other things they haven't identified here, Wolf, but I spoke to an analyst today who said they looked like defensive positions. All of this adds up together to something that looks very much like a military installation.

I just remind you that the president of China, Xi Jinping, had a promise to President Obama last fall, he would not militarize. It looks like the facts on the sea are very much opposite to that.

BLITZER: You've been all over this since that report and you did last year which was nominated for an Emmy, Jim Sciutto. Congratulations on that amazing reporting by our own Jim Sciutto.

SCIUTTO: Thanks very much.

BLITZER: And now a CNN exclusive: secret battles against ISIS revealed thanks to heroic actions by U.S. forces.

Our Pentagon correspondent, Barbara Starr, has this story.

Barbara, these were some highly classified missions.

BARBARA STARR, CNN PENTAGON CORRESPONDENT: Wolf, the battle against ISIS has largely been waged in secret by U.S. Special Operations Forces. The battles far from the public view, but now tonight here in THE SITUATION ROOM, we have new details.

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STARR (voice-over): Navy SEALs in a fire fight against 100 ISIS operatives in Iraq. This cell phone video captures a rare glimpse into the deadly world of special operation the public is never meant to see. Navy SEAL Charles Keating was killed here.

Across the ISIS battlefield, U.S. Special Operations are engaged in missions so perilous, it's become a secret dossier of courage in the fight to kill ISIS. CNN has learned, there are four silver stars, the third highest award for valor for combat against ISIS that are so classified no details are available. None.

But clues on other battles are emerging from documents obtained by CNN detailing the combat awards for missions never fully described in public. One filed details exclusive new information on a July 2014 raid that so far has only been briefly acknowledged. A Silver Star was awarded to an army helicopter pilot for a 10-hour classified, high-risk mission deep inside enemy territory. The pilot flew overhead for five hours after being wounded during the initial assault.

The mission, Navy SEALs and Army Delta Force commandos had tried to rescue American hostages being held by ISIS in Raqqah, Syria, including journalist James Foley later murdered. The Americans had already been moved.

We now know how tough a fire fight that was. A marine was awarded a bronze star as he came into close combat with ISIS and eliminated a grave threat. And from May 2015, significant new detail about a raid inside Syria to capture a top ISIS operative named Abu Sayyaf. He was killed in a fire fight. For that raid, a Silver Star secretly awarded to an army pilot for a nighttime high-risk mission deep inside enemy territory.

He continued to fly for over an hour despite sustaining intense battle damage to his aircraft during the initial assault.

CNN is withholding names of the troops involved at the request of the Pentagon, but we are revealing their valor.

PAT MULCAHY, DIRECTOR, OFFICER AND ENLISTED PERSONNEL MANAGEMENT: Twenty percent of the awards are not in the public domain, whether they were in a classified operation or a number of the special forces and thus, for security reasons, we don't publish.

STARR: Over 240 awards for the battlefield since 9/11 are still stamped classified.

President Obama also secretly awarded medals to the Navy SEALs that killed Osama bin laden. Former SEAL Jeffrey Eggers was there and recalls an extraordinary scene.

JEFFREY EGGERS, NEW AMERICA FOUNDATION: It was the humility of the military forces that were there, the fact that they were trying to deflect credit elsewhere.

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STARR: Let's come back to where we started, Wolf. Since 9/11 over 240 awards for valor to American service members in secret because the missions they have been on are so classified and so dangerous, it is a breathtaking dossier of courage and valor on the battlefield.

BLITZER: And as you say, there have been hundreds of these awards since the 9/11 attacks. The Pentagon is taking a closer look at all of them?

STARR: That's right, Wolf. They are, in fact, reviewing all 1,200 awards for valor since 9/11. Many in public, some not, but they're going back through all of the files now because they want to make sure that all service members got the awards and the recognition that their acts deserved on the battlefield. Some of them may be upgraded -- Wolf.